列车运行控制仿真系统-轨道电路模块的设计与实现

ZPW-2000A无绝缘轨道电路由较为完备的轨道电路传输安全性技术及参数优化的传输系统构成,为"机车信号做为主体信号"创造了必备的安全基础条件.本文对轨道电路状态和轨道码序仿真为CTCS2级列控系统的实现创造了必要条件.     

GJB 5000A三级OT过程域实施

文章通过介绍组织培训的基本流程,重点解读了GJB5000A三级OT过程域对于组织培训的要求。基于GJB 5000A三级组织培训(OT)过程域的要求,分析了组织培训的实施要点和注意事项。根据相关实施要点,并通过一段时间的组织培训实践,提高了整个组织的软件工程化水平和软件开发能力。     

主机排气阀座脱落和漏水的原因探析

分析某船韩国制造的L28／32A型主机气缸盖排气阀座在运行中脱落和进、排气阀座漏水的故障原因,在此基础上阐述具体的处理方法,并就同类故障的修理提出对策措施。     

缺锌儿童血清维生素A含量和5＇核苷酸酶活性观察

观察缺锌儿童血清维生素Ａ（ＶｉｔＡ）含量和５＇核苷酸酶（５＇－ＮＴ）活性的变化。结果表明，缺锌儿童血清ＶｉｔＡ含量和５＇－ＮＴ活性显著低于健康对照者（Ｐ＜０．００１）。锌剂治疗两月后，随着血清锌水平的提高，ＶｉｔＡ含量和５＇－ＮＴ活性明显升高。提示缺锌可影响小儿体内ＶｉｔＡ和核酸代谢。     

肾移植患者应用更昔洛韦后环孢菌素A的药动学及临床生化指标的研究

对１０例肾移植患者应用与未用更昔洛韦后环孢菌素Ａ的药动学参数及临床生化指标进行研究。采用荧光偏振免疫法测定血药浓度,３Ｐ８７程序拟合药动学参数。结果显示：应用更昔洛韦后,环孢菌素Ａ药动学参数Ｋｅ、ｔ１／２（Ｋａ）分别由未用组的（０．１６±０．０４）ｈ－１和（１．３９±０．７６）ｈ降至（０．０９±０．０５）ｈ－１和（０．５０±０．３２）ｈ（Ｐ＜０．０５）,Ｔｍａｘ由（３．６７±０．７７）ｈ减至（２．００±０．７８）ｈ（Ｐ＜０．０１）,ｔ１／２（Ｋｅ）由（４．０８±１．８５）ｈ增至（１０．５１±６．４２）ｈ（Ｐ＜０．０５）,峰浓度Ｃｍａｘ平均升高２７％。肾移植后应用更昔洛韦组肾功指标下降,肝功指标上升,其中血清肌酐、总胆红质与未用组相比有统计学意义。表明更昔洛韦使肾移植患者环孢菌素Ａ的药动学参数及临床生化指标发生改变,提示临床调整用药方案。     

重组腺伴随病毒载体表达hBDNF对大鼠基底前脑胆碱能神经元损伤的保护作用

目的　探讨重组腺伴随病毒载体表达人脑源性神经营养因子 (hBDNF)对大鼠基底前脑胆碱能神经元损伤的保护作用。方法　用 β淀粉样肽 (Aβ2 5 3 5)注入大鼠Meynert核损伤胆碱能神经元。损伤后 8～ 10d行hBDNF重组腺伴随病毒脑内注射。经避暗回避试验测试大鼠学习记忆能力 ,组织学及免疫组织化学观察hBDNF表达以及胆碱能神经元数量变化。结果　避暗回避试验结果显示 ,应用hBDNF重组腺伴随病毒 4周后 ,实验组动物的学习记忆能力增强 ,行为明显改善。胆碱乙酰转移酶 (ChAT)免疫组织化学染色显示 ,注射点附近免疫反应阳性神经元散在或成群分布 ,数目明显增多 ,经与模型组比较 ,胆碱能神经元数量增高约 3 7%。结论　hBDNF重组腺伴随病毒可在脑内表达hBDNF ,表达的hBDNF对损伤的胆碱能神经元具有营养和保护作用。     

Oleanolic acid-induced apoptosis and its relation with intracellular calcium in human lung adenocarcinoma A549 cells

Objective To investigate the effect of oleanolic acid (OA) on apoptosis, correlation between apoptosis and intracellular calcium, and its mechanism in human lung adenocarcinoma cell line A549. Methods Human lung adenocarcinoma A549 cells were incubated in vitro and assigned with OA concentrations of 0, 10, 20 and 40μg/mL. The apoptosis status of A549 cell line was detected with Annexin V-FITC/PI by flow cytometry (FCM); fluorescence intensity (FI) of A549 cells was assessed and the level of intracellular calcium was calculated at 24 hour of OA intervention. The relation between apoptosis and calcium FI was illustrated by curve fitting. Results FCM showed that 10, 20 and 40μg/mL of OA could induce A549 cell apoptosis, which followed a concentration-effect pattern; 24-hour intervention with 20μg/mL and 40μg/mL OA showed increased A549 cell apoptosis, and was significantly different from that with 0μg/mL OA (P<0.01). The FI of intracellular calcium concentration in 10, 20 and 40μg/mL OA groups was significantly higher than that in 0μg/mL group after 24 hours' intervention, and the FI showed a trend of increase with increased OA concentration (P<0.01). Curve fitting showed a significant correlation between apoptosis rate and intracellular calcium concentration in A549 cells (r=0.981, P<0.01). Regression equation was Y=0.508X-1.627. Conclusion OA plays a role in inducing apoptosis of human lung adenocarcinoma cells in a concentration-dependent manner. The OA-induced apoptosis is responsible for intracellular calcium overload of the tumor.     

ZPW-2000A三接近区段存在的问题及解决方案

就ZPW-2000A自动闭塞系统电路三接近区段存在的问题进行了具体分析，提出解决问题的方法，确保行车效率和行车安全。     

美国铁路重载运输

介绍了美国铁路重载运输的现状.